Balance assembly gauge



June 30, 1953 GARQN 2,643,462

BALANCE ASSEMBLY GAUGE Filed Jan. 8, 1952 I INVEN TOR. I Tobias Ga on Patented June 30, 1953 [TED STATES PATENT OFFIC BALANCE ASSEMBLY GAUGE v Tobias Garon, Detroit, Mich.

Application January 8, 1952, Serial No. 265,404

1 Claim.

This application discloses a Balance Assembly Gauge, particularly useful to a watchmalrer for properly assembling a balance assembly.

A balance assembly includes a hair spring having a stud and hub or collet, and a roller table having a roller jewel, both mounted, with a balance wheel between them, on a balance staff. In assembling the hair spring on such staff, already having a roller table and balance wheel thereon, care must be taken in insure that the hair spring stud is positioned properly with respect to the roller jewel. The gauge hereof provides such insurance.

For a full understanding of thegauge hereof, reference should be had to the appended drawing.

In this drawing:

Fig. 1 is a top plan view, to full scale, of the gauge, with some radiating lines thereof omitted for purposes of clarity.

Fig. 2 is a part section view as if on line 2--2 of Fig. 1.

Fig. 3 is a greatly enlarged plan View showing the gauge in use, with parts omitted and fragmentarily shown for purposes of clarity.

Fig. 4 is a section view on line 44 of Fig. 3.

Referring now to the drawings, it will be seen that the gauge herein shown comprises a thin, gauge plate Ill formed with an integral downwardly turned flange H which supports plate I!) well above a work table 12 to provide a clear space it beneath plate Hi.

Formed in plate It is a triangular opening l4, long and narrow, with a base l5 and sides It joining to define a small angle V or apex IT. on said plate is a pattern of gauge lines 18.

In the embodiment shown, the pattern of gauge lines includes sixty radiating lines, all continued to their center, a point [9 within the V and near apex I7, and disposed at six degree intervals, and numbered l-60. For purposes of clarity, only a few are shown, and only a few of these are shown complete and numbered.

A watchmaker has an assembly comprising a balance staff 20, a balance wheel 2! and its balancing screws or pins 22 and arm or hub 23, a hair spring 24 with its stud 25, and a double roller table 25 with its safety roller 2'! and its jewel 2B.

The roller table may be a single plate, omitting safety roller 21, or it may be double, as shown, to include the safety roller 21. The latter form is very widely used, and is shown here, since a gauge that will accommodate a double roller plate will, of course, also accommodate a single roller plate, though the reverse is not true.

In Fig. 3, only a part of the hair spring 24 is 2 shown, the major and center part being omitte for purposes of clarity. The hair spring in its entirety simulates a flat thin disc of a diameter less than that of the balance wheel, and has a center hub or collet enabling it to be mounted on the staff 20.

When the watchmaker begins his work on the balance assembly, he first places such assembly on the plate in such a position that the roller table safety roller 21 enters the large base part It of opening I4 and then he slides the assembly around and along the plate until he has positioned jewel 28 as far as it can go into the apex 11.

It is noted that the apex I! and the sides I6 of the opening M are so dimensioned, in relation to the size of the jewel 28 and staff 2!], that with the jewel as far as it can go intoapex 11, the axis of balance staff 20 approximately coincides with the center point l9. With the assembly in opening M, the sides of such opening securely hold the assembly from laterally shifting to any appreciable extent, either because both the jewel 28 and the staff 20 are engaged by such sides, or because one of them is engaged, and the other is very close to such sides. In most cases, staff 20 will be engaged by sides [6 of opening M, with jewel 28 very close to such sides.

The watchmaker, having moved jewel 28 as far into apex I! as it can go, then notes the position of stud 25 in relation. to the position of jewel 28 by noting which one of the radiating lines It coincides with the axis of stud 25. In Fig. 3 the stud axis is between lines 39 and 40.

Then the watchmaker, remembering the fact that the stud axis was at 3940, is free to disassemble the balance assembly for repair or replacement of any part, and then to reassemble the parts, at least up to the point where he is about to restore a hair spring to a balance staff already provided with a roller table and a balance wheel. He places such assembly on the gauge, enters safety roller 21 into opening I 4, and moves the assembly to seat jewel 28 in apex I l as far as it can go. He then mounts a hair spring on the staff and moves the hair spring around until its stud 25 is positioned with its axis between lines 39 and 4!]. With the stud properly located, the assembly may be removed from the gauge with the assurance that stud 25 is properly located with respect to jewel 28.

Since it is important that the opening Hi be so shaped as to inhibit totally or almost totally any angular shifting of the assembly in such opening, and since it is important that opening l4 have an enlarged part l5 capable of receiving Altitude of opening l4 inch Base I5 of opening l4 1%- inch Distance from apex I! to center point [9 inch Sides N5 of opening |4- Equidistant from the Y altitude, i. e., 0p ening 14 is an isosceles triangle.

It is noted that whereas Fig. 3 shows jewel28 in apex I! as far as it can go, Fig. 4 shows jewel 28 remote from apex H, but moving towards it, in the direction of the arrow.

Now having described the gauge hereof, reference should be had to the claim which follows; 1

A balance assembly gauge for watchmakers comprising a sheet metal gauge plate, and de-' pending side-fiangemeans mounting it in a manner-t0 provide a clear space beneath it, the gauge plate having an opening, two of whose sides join to definea V or apex of'small.angu1arity,said plate having thereon a plurality of gauge lines radiatingfrom a point on said plate, said point from. which the lines radiate being within. the V Number I or apex of the opening, the opening having an entry portion at least large enough to permit entry therethrough from above the plate, of the safety roller portion of a double roller table of an assembly of a balance wheel, double roller table, roller jewel, hair spring, and balance staff, whereby the roller jewel of said assembly may be positioned in the V or apex of the opening, and the circular? relation .or positioniof, thehair spring stud disposed above the,plate,.with respect to said jewel then in the apex, may be indicated by the. registry of said stud, above the plate, with one or another of the various radiating lines on said plate, beneath said stud, the clear space un der said plate provided by said flange being high enough-toenable the safety roller of the double rollerrtableto fit beneath the plate when the jewel thereof is within the apex.

TOBIAS GARON.

References. Cited, in the-fileof, this patent UNITED STATES PATENTS Name Date Wathier, Feb. 5, 1884 London July 7, 1891 Allison; Sept. 14,1909 

